摘要:Purpose: The persistence of this research was to conclude the relationship and impact amongst the variables which includes i.e. Trust, perceived usefulness and Purchase intention,(independent construct) on online buying behaviour of e-pharmacy through social media influence (dependent variable) across the developed and emerging countries i.e. United States, United Kingdom and India. Researcher used big – data modelling approach to predict whether the Millennial will get influenced or not influenced with the social media towards e-pharmacy. Design/methodology/approach: A structured questionnaire covered descriptive inquiries, five point Likert scale questions, and qualitative questions to collect data from respondents who were SSC/HSC, UG(under graduate) and PG (Post Graduate) scholars across India, USA, and the UK. As a methodology, Partial least square structural equation modelling was used for Data Analysis. We collected data from India, USA, and UK from the Millennial group, accounting for nearly 34 %, 40% and 35% of the inhabitants respectively. The growth of the online retail sector has increased due to the usage of internet for searching by the youngster. E-retail sector is predicted to upwelling from 3% of the whole Indian retail marketplace in 2017 to 7% by 2021. Similarly, for USA surge from 6 %of overall US retail market in 2017 to 15% by 2021 and UK come from 5% of total US retail market in 2017 to 12% by 2021. These show a positive sentiment for the online pharmacy industry to gain momentum in the coming years in these countries. Findings: The outcomes show that trust is more important parameter and influenced by the social media in the UK context, but it is not playing a significant role in USA and India context through social media. Perceived usefulness, perceived intention and demographics are influenced by the social media feedback posted across different cultures which impact online buying behaviour of medicine (e-pharmacy). Practical Implication: This study will be benefited for the retail sector managers to plan the strategies for communication to target Millennial more effectually and design their advertising campaigns that can influence their belief and purchasing activities in a positive way. Originality/Value: This research paper highlights the use of Techno.